New York Mayor Michael Bloomberg sought Tuesday to ignite debate over immigration among the presidential contenders, saying there was no faster or cheaper way to fix the nation’s economic problems than by abandoning “self-defeating” immigration policies.

In an editorial published Tuesday and at appearances before business leaders in Chicago and Boston, Bloomberg laid out some of his ideas, saying immigrants and the businesses they create are engines for America’s economic recovery.

He spoke alongside William Daley, President Barack Obama’s former chief of staff, before heading East to a similar forum discussion with conservative media mogul Rupert Murdoch.

“If Bill and Rupert can find common ground - and they can - there’s no reason Democrats and Republicans in Washington should remain burrowed in their partisan foxholes,” said the editorial by Bloomberg, a Democrat-turned-Republican-turned-independent.

Bloomberg has long argued that the United States is committing economic suicide by sending the nation’s top international students and the world’s most promising entrepreneurs to other shores. In Chicago, he pointed to a study released Tuesday by a partnership of U.S. mayors and business leaders that he co-chairs, which found, among other things, that immigrants were responsible for one out of four new businesses started last year.

“I know of no ways to help our economy as quickly and as cost-free as opening up proper ways to people who will come here, create jobs, create businesses, help our universities,” Bloomberg said. “Immigration is what built the country, immigration is what kept this country going for the last 235 years and now we seem to have walked away from it.”

In his editorial, published by the Bloomberg News service he owns, the New York mayor said the United States was falling perilously behind other nations in wooing skilled immigrants. He presented some specific proposals: green cards for top foreign graduate students at U.S. colleges, a much higher percentage of green cards awarded on the basis of economic needs, a visa specifically for entrepreneurs and a guest worker program for seasonal labor.

He also advocated a path to citizenship for the millions of illegal immigrants in the country.

During the Boston forum, Murdoch called it a “scandal” that temporary work visas send highly skilled graduates away after a certain amount of time in the U.S. If an immigrant graduates from college in a science, technology or math field, Murdoch said, he or she should have a green card stapled to the diploma.

Bloomberg and Murdoch pressed the two presidential campaigns to detail proposals on immigration.

Obama pledged in 2008 to push for passage of comprehensive changes in immigration laws, but the effort stalled in Congress. Obama then issued a directive in June that protects immigrants who were brought to the United States illegally as children, exempting them from deportation. The policy grants temporary work permits to those who apply, but it does not provide a path to citizenship.

Republican challenger Mitt Romney has criticized the directive but has not said whether he would reverse it, pledging instead an unspecified “civil but resolute” long-term fix to illegal immigration.

During the Boston forum, Bloomberg, who has belonged to both major parties, called the Republican tendency to oppose immigration changes “one of the dumbest strategies” he had ever heard of.

The Australian-born Murdoch said that if Romney courted a pro-immigration stance, it could actually help his chances of winning the presidential bid because many Hispanic immigrants tend to be socially conservative.

Whoever wins the presidential election, they said, will need to get a handle over Congress and force lawmakers to work together in the interests of the country.

“Brilliant gutsy people, leaders, make investments when times are tough and leaders bring along other people,” Bloomberg said.